Daemon

I've got a manual '95 runner with a 3.4 swap from a '98 that I bought used
from a member of this forum. I've recently discovered that my
front wheels are not engaged in 4wd mode either in 4HI or 4LOW.
I know it used to work (saw em all spin in a snow drift this winter)
and does not now. The 4WD light comes on, but no drive up front.
Found this out while descending a very steep hill and almost ended up sideways with the rear tires turning very slowly and the front
freewheeling. Fun. Much further testing shows it's just dead.

I started with this thread https://www.yotatech.com/forums/f116...gaging-115596/
and followed the troubleshooting links there, which
among other things say that with ADD two things must be true
for the 4WD light to come on. The shift lever has to be in
a 4WD position *and* the switch in the ADD actuator
must detect that the sleeve has been pulled toward the
passenger side, engaging the front half shafts.
Since my 4WD light is coming on, that would imply that ADD is
operating correctly, but I'm not getting drive from the transfer case.

Any thoughts on what else could be going on here? If I'm not
getting drive from the transfer case, then we're pretty much
talking mechanical failure somewhere right?

ian

Daemon

Hmm, little quick investigation shows that the wires/harness to the plug for the
ADD sensor in the actuator mechanism is missing. Realized it had to be
when I was able to get the 4WD light to come on with the engine
not running (no vacuum).

Guess that's good news as it means it's probably back to a vacuum
line problem or something wrong with the signal to the actuator.

ian

Daemon

Ok, figured it out.

There's two vacuum lines that run from the solenoid on
the driver's side, across the diff to the passenger side
and upwards. Mine look a bit cobbled, and they were
hanging down and rubbing on the passenger side inner CV coupling
bolts. Both lines are worn halfway through and now non-functional.
Amazing that they lasted as long as they did. Hopefully
a small splice, few vacuum connectors and some heavy duty zip ties
will sort this out for good.

ian